


Uninvited but not unwelcome

by alicedragons



Series: Heat Wave [4]
Category: Undertale (Video Game)
Genre: (Very mild), Bottom Twist, Brief sexual anxiety, Character using both sets of genitals, Cuddling, Explicit Sexual Content, Heat Fic, Implied threeway, M/M, Mating Cycles/In Heat, Penetrative Sex, Shower Sex, Smut, Top Cash
Language: English
Status: Completed
Published: 2019-02-20
Updated: 2019-02-20
Packaged: 2019-10-31 21:08:00
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,902
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17856980
Author URL: https://archiveofourown.org/users/alicedragons/pseuds/alicedragons
Summary: Cash doesnotneed help from the likes of Twist.Maybe he does. Just a little.





	Uninvited but not unwelcome

**Author's Note:**

> TwistedMoney requested by anonymous on tumblr! Part 4 of the heat series. I threw a bit of TwistedPuppyMoney in, but the smut is focused on TwistedMoney. I don't think there's anything I need to warn for, but I will mention that Cash is a stubborn boy.

Not that he’d ever tell them, but Cash didn’t really mind having Twist and Slim over. They showed up every week (completely uninvited) and Cash was forced to provide them with dinner and company (and sex, usually). He put up a fuss—it was very impolite of them, after all—but for all his grumbling, there was a treacherous part of him that was always disappointed when they left.

“Heya, Patches!” Twist bounded through the door and stifled Cash with a hug—which he rejected, ducking out from under his arm with a growl.

“we brought dessert!” Slim said cheerfully, slipping in behind Twist and heading into the kitchen. Wrenching himself free of Twist, Cash followed him.

“what is it?” he asked snidely. “twist’s dick?”

“ _and_ pavlova,” Slim said, smirking at Twist, who purred and pressed himself against Cash’s back. Cash allowed a few neck kisses before pulling himself free of Twist’s arms. Eyeing the store-bought pavlova, he hummed.

“fine,” he said, giving a disinterested wave of his hand. “you can stay.” Twist and Slim exchanged a triumphant grin—which Cash pointedly ignored.

Normally he was more than happy to indulge them in a little dinner conversation, but tonight, he was itching for dessert— _real_ dessert, not the boxed treat waiting for them in the kitchen. He wasn’t the type to leave the kitchen messy, but right now he just—couldn’t be bothered. There were other things on his mind. He had his mouth on Slim’s jaw before he’d put his plate in the sink. “oh, already?” Slim laughed in soft surprise—though he certainly didn’t seem to mind, his hands wandering.

“Aw, eager tonight, darlin’?” Twist murmured, looking up. Never one to be left out of the action, he stood up and sandwiched Cash from behind while he and Slim kissed. “Mm, yer nice an’ warm,” he purred, nuzzling into Cash’s neck. Slim cupped his crotch and he grunted. The touch was scarcely enough, but the relief was immense. He bucked into Slim’s hand, magic dropping to his pelvic cavity. Patience running out, he ‘ported them to his room.

The sex was always good with the three of them. It was warm and relaxing, like climbing into bed after a hot bath. Only tonight, it also left him a little wanting… and warmer than normal. When Slim rolled off him and Twist curled against him from behind, Cash was of half a mind to ask them to keep going. There was still… an itch inside him. A prickle of need. He felt hot and bothered, and he squirmed in Twist’s arms.

He managed a few restless hours of sleep, but awoke when the ache in his bones became too much to tune out. The clock on his dresser read one, and the prickle had grown to a burn. He was sweating so much, his sheets felt damp, and he could smell himself. Sharp and salty and sweet.

Slim had his back to him, and his chest rose and fell steadily, still deep asleep. Cash writhed and turned over. Twist was awake, and watching him, his single eye-light bright in the gloom. “Look like ya could use a hand,” he said quietly.

Cash growled and scrambled over him to get out of bed. “i’m fine,” he grunted. “gonna take a shower.” He knew exactly what was happening, and he wished he’d recognised it earlier, so he could have asked Slim to come alone. He didn’t need _Twist_ of all people helping him out of pity.

“Darlin’...” Twist spoke gently, resting a hand on Cash’s shoulder. “It ain’t gonna go away on its own. Lemme help.”

“i said i’m fine,” Cash snapped, brushing his hand off. “just… leave me. i can handle it.” He wiped a hand across his forehead and staggered into the hallway, reaching through the darkness for the light switch. When he flicked the passage light on, it was too bright, and his head throbbed. He leaned against the bathroom doorframe and pressed his cheek against the cool tiles. They misted beneath his heat.

He heard Twist’s footsteps behind him and scowled, turning on the shower as cold as it would go. He didn’t waste time taking off his clothes, climbing straight in and sitting on the floor when his legs refused to keep him up. He tipped his skull back and let the icy water rush over him, shivering. It was a shock to his overheated body, but inside, his soul was still heavy and simmering, magic building quickly within. He pressed his forehead against his knees, inhaling slowly. A clench of pain in his chest made nausea wash over him.

There was a wet _thunk_ against the tiles as Twist sat behind him. Cash lacked the energy to protest when he placed his legs on either side of him, resting comfortably against his back. He hated that just the press of him against his coccyx made his soul squeeze. Magic dripped through his chest cavity. “twisted,” he groaned. “please…” He didn’t know what he was asking for—anything, really. Just not this. This burning ache.

“Please what?” Twist was uncharacteristically soft and tentative. “You wan’ me ta go?” Cash shook his head, taking another gulp of air, as if it might quench the heat.

“no—don’t.”

“Stay?”

Cash nodded, and with a lump in his throat, said, “help me.”

Twist nodded. “Tha’s all I wanna do. Wanna make ya feel good. Make ya comfortable an’ happy. Alright, darlin’?”

“you don’t have to tell me, just do it!”

Twist stroked his arm, soothing him with soft words. “Easy… I’ve got ya. Don’ worry ‘bout anythin’, just relax and lemme take care a’ ya.” He reached into Cash’s pyjama bottoms and cupped his pelvis. “How’s this?” he asked, rubbing the bone slowly. Cash swallowed and nodded. Magic coalesced in the area, clinging to Twist’s fingers until Cash formed a cock. “Tha’s it, sweetheart. Let’s see what we can do with this, yeah?” He palmed Cash, slicking him up with his own magic. His cock pressed against Cash’s lower spine, and Cash inched further into his lap, craving the touch of it.

Twist carefully undressed him and used his clothes to cushion the shower floor. He rested Cash on his back and knelt over him. “This good?” Cash nodded stiffly, bucking his hips into Twist. Below his cock, he could feel the soft folds of Twist’s cunt.

“wanna be inside you,” he murmured, his face heating before the words had even left his mouth.

“Yeah?” Twist sank low enough for the head of Cash’s cock to brush his outer folds. “Like that?” Cash shut his eyes, nodding frantically.

“twist…”

“I’m gonna make ya feel so _good_ , sweetheart.” Twist leaned down and brushed their teeth together. His breathing was heavy against Cash’s mouth, and he exhaled sharply when the head of Cash’s cock breached him. He kissed Cash deeply, gradually lowering himself onto his cock. But it still wasn’t _enough._

“twisted—more,” Cash whined, forgetting his composure. “please, i need—” He broke off in a groan as Twist took him deep. He was tight, and pleasantly cool in contrast to the burn of Cash’s magic. Relief trickled through him, and magic leaked from his chest and into the water. As Twist rode him, the knot in his soul loosened.

He’d never had much stamina, and his heat only furthered the fact. He came hard, moaning and spilling into Twist. Magic leaked down Twist’s femurs and he sighed. “Fuck, feel good, precious? Yer makin’ me feel good, y’know. Love seein’ ya come like that. Seein’ the look on yer face.” He hummed and bent down, nuzzling into Cash’s neck. Cash turned his face away to hide his blush.

“twist,” he whined softly. “keep going. please…”

“Mm, hold onto my hips, darlin’.” Cash did, rubbing his thumbs over the coarse bone. Twist’s breaths were quick and shallow. He reached between them and pumped his cock as he rode Cash, his mouth still exploring Cash’s neck. Cash groaned as the muscles of Twist’s cunt began to tighten around his cock, the pressure inside him building once more. “Fuck—fuck! I’m…” Twist gasped, cupping Cash’s jaw and kissing him hard as he spurted magic across his spine and lower ribs. Cash moaned into his mouth, a burst of pleasure rocking him as he came again.

Twist slumped onto his chest, breathing heavily against his shoulder. Cash squirmed beneath him, still far from satisfied. “twisted…”

Twist exhaled, squeezing Cash’s arms and planting a kiss on his sternum. “Gimme a minute.” He sat up slowly and shut his eyes, swallowing. “Fuck. Ya got no right makin’ me feel that good.” The corner of Cash’s mouth twitched, but he said nothing. Twist smiled and brushed his fingertips over Cash’s ribs, then hesitated, his lit eye hovering over the centre of Cash’s sternum. “Sweetheart… do you wanna…?” Cash frowned, looking down, and his chest immediately seized.

His soul glowed prominently through his ribcage, slick and dripping with excess magic. He looked at Twist, frantically pulling his arms around himself. “no! no, i—i didn’t mean to—no! no, no, no—it’s not—”

“Take it easy, shh, calm down, sweetheart. Breathe with me—in.” Twist inhaled and Cash matched him. “Out.” He exhaled slowly and Cash followed, his panic slowly easing. When he’d settled, Twist took his hand and stroked his fingers, saying, “I ain’t gonna force ya ta do anythin’. ‘Specially not that. I just thought—” He shook his head. “You ain’t gotta do anythin’ tha’s gonna make this harder fer ya. You wanna keep goin’?” Cash nodded, eager in spite of himself. “Good.” Twist kissed deeply and took him in again.

He didn’t ask for an explanation, and Cash was relieved—he didn’t really have one. He wasn’t sure why his soul had manifested. It sometimes did, during heats, but usually when he was alone, and only upon command. Not with other people, and certainly not with Twist. He couldn’t explain it, nor did he care to ponder it. Twist continued as if it hadn’t happened, and Cash was happy to leave it at that.

When the water started to feel too cold, Cash squirmed underneath Twist, pushing him away. “Had enough?” Twist asked. The water had washed away the sweat and cum and spent magic, but Cash still felt a mess.

He nodded, sitting up. “yeah. i’m done.” Twist smiled and climbed off him, turning the shower off. This was normally the point at which Cash would pull away and go outside for a smoke. Perhaps it was his lack of energy, or perhaps it was because he just needed to feel ~~wanted~~ safe for a little longer, but this time, he let Twist wrap him in a towel and take him downstairs.

Twist lit a fire in the hearth and lay on the carpet next to Cash, sharing the towel. Their bare bones pressed together, and Cash shut his eyes to avoid Twist’s gaze. The fire crackled and spread warmth across them, the sound of it lulling Cash into a doze.

“I know we’ve been at it fer hours,” Twist murmured, “but this is kinda gettin’ me in the mood.”

“shut up and let me sleep, you asshole.”

Twist smiled, kissing Cash’s skull. “Is cuddlin’ allowed?”

Cash sighed, and nodded. “just this once.”

Not that he’d have it any other way, he thought, as Twist held him.


End file.
